Genetic analysis is implemented as an important tool in the monitoring of large carnivores in Scandinavia. In particular, DNA analyses of carnivore scats are extensively used. Over the last decade, wolverine scats have been routinely collected and analysed over large parts of the distribution range in Norway and Sweden. Identification of individuals from DNA profiles of the collected samples has provided an increased understanding of population size, reproduction, population structure, and immigration.

Here, we report on the number of individuals identified in Norway, Sweden and Finland during winter 2015. The number of identified individuals represents a minimum estimate of the population size. It is not yet clear what proportion of the true population size these minimum numbers represent. However, the proportion must be quite high in Norway, given the generally good sam-pling coverage, a large number of analyzed samples, and a very high proportion of known individuals among culled adult wolverines. In Sweden, there is a rather long way to go in order to obtain representative sampling across the entire population. As such, a stronger focus on DNA sampling is needed in most counties over the next few years.

In 2015, 269 wolverines were registered within the national borders of Norway, which is a con-siderable reduction (17,5 %) from 326 wolverines identified from DNA in 2014. The number of samples analysed was also substantially reduced between 2014 and 2015. Thus, without cap-ture-mark-recapture (CMR) based estimates of population size, it is difficult to evaluate whether these numbers represent a true population reduction. In Sweden 238 wolverines were identified from DNA in 2015, which is a small increase from 221 wolverines in 2014.

It is a central goal in the monitoring of Scandinavian wolverines to use CMR based methods to estimate the population size. A large number of models with partly different basic assumptions have been developed. However, to adjust the applied models to the Scandinavian wolverine population, some revision are needed. In particular, wolverines living close to administrative borders such as countries, regions or counties create challenges. We have tested a recently developed model, but the analyses revealed weaknesses in the modelling, especially when the num-ber of samples varied strongly among years. The academic council for the National monitoring programme recommended combining spatial and temporal aspects in a more integrated way. In such a model, it will still be possible to focus on individual home ranges to handle the challenges related to administrative borders and open populations, but at the same time use the sampling history for individuals to reduce the model’s sensitivity to variation in sample size between years.